How Hospitals Can Protect Frontline Healthcare Workers From COVID-19
Lessons From Successful Model Countries
Ken Jung · Ron Li · Andrew Ng · Christian Rose · Eric Topol · Kelly Zhang · Ming Zhou · Sharon Zhou
Stanford University & Scripps Research Translational Institute
We need health-care workers to care for the sick, even though their jobs carry the greatest risk of exposure. How do we keep them seeing patients rather than becoming patients? — Atul Gawande, The New Yorker, 3/31/20
Healthcare workers (HCWs) are at high risk of becoming infected with COVID-19, and many are already falling ill or dying. We need to understand what hospitals in countries with low rates of HCW infections did right, and what lessons can be brought to frontline HCWs in the United States.
Their success comes not just from the availability of personal protective equipment (PPE), but also from the high level of rigor with which hospital infection control processes are applied, and a shared understanding that protecting HCWs is core to fighting COVID-19.
Sourcing information from documents and interviews with infection control experts from successful model countries, we summarize key lessons in hospital infection control for COVID-19:
- Minimize the entry and movement of the virus within hospital walls
- High standards for PPE strategically tailored for different levels of exposure risk
- Comprehensive staff screening and management strategies that minimize transmission risk while maintaining a viable workforce
We believe the principles behind these lessons can inform how we approach infection control in the United States.
Control movement of virus into/within the hospital
Hospitals can establish distinct regions that are physically separated based on risk of viral exposure. The purpose is to know and control how the virus moves within the hospital.
- Low Risk: non-patient care areas, ambulatory care areas, and medical wards housing asymptomatic non-COVID patients. HCWs can assume a low risk of exposure to the virus.
- Moderate Risk: Screening and triage clinics, medical wards housing clinically stable suspected or confirmed COVID patients who are not receiving high risk procedures, such as intubation, bronchoscopy, and other intensive procedures that may aerosolize viral particles. HCWs can assume exposure to the virus primarily via droplet and fomite, but airborne transmission is less likely.
- High Risk: Intensive Care Units (ICUs) and procedure rooms that house severely ill suspected or confirmed COVID patients. HCWs assume a high risk of exposure to aerosolized viral particles generated from procedures and patient symptoms such as severe cough, vomiting, and diarrhea.
Moderate and high risk zones are geographically consolidated and isolated from the rest of the hospital. Establishing and maintaining distinct geographic zones based on risk of viral exposure limits the movement of the virus within hospitals and enables efficient allocation of PPE and HCW resources to where they are most needed.
Below we describe three key aspects infection control at these hospitals:
- What policies and processes can minimize infection risk within and between zones?
- What kind of PPE is needed to protect HCWs in each zone?
- How are HCWs screened and monitored for COVID-19?
Policies and Processes for Each Risk Zone
Low Risk
- Prevent contamination on entry and exit. Patients and staff who are asymptomatic and have no history of close contact with suspected or confirmed cases enter the hospital and proceed to low risk zones along dedicated routes that avoid travel through moderate and high risk zones. They are also screened with questionnaires and body temperature monitoring. Suspected COVID-19 cases are directed away from low risk zones into separate areas of the hospital. Clear signs and physical barriers reduce unnecessary traffic that may facilitate spread of the virus.
- Keep non-urgent and routine care patients away from the hospital. Hospitals are seen as potential sources of viral transmission. Routine care is conducted either remotely, through phone or video, or at screening areas physically separated from the main hospital.
- Implement social distancing and risk mitigation in ambulatory care. Risk of asymptomatic transmission is taken seriously. Social distancing measures such as separating seating areas in waiting rooms, installing transparent droplet barriers between staff and patients in reception areas, and prohibiting individuals from sitting facing each other in the cafeteria, which is seen as a particularly high risk area for transmission.
Moderate Risk
- Prevent spread of the virus on fomites such as PPE and clothing. HCWs exiting moderating risk zones risk carrying the virus via fomites. Many hospitals minimize this risk by setting up clearly marked, designated, access-controlled exits. Buffer zones are set up at the exits in which HCWs can carefully doff (take off) PPE so that potentially contaminated PPE does not enter low risk zones.
- Prevent spread of the virus from infected patients during transport. Infected patients being transported outside of their isolation rooms are at high risk of contaminating their environment and surrounding HCWs. Dedicated, clearly marked routes for transfer minimize risk of contamination. In certain situations, patients are transported inside mobile isolation units, with the transportation staff in full PPE (“bunny suits” with PAPRs).
- Implement workflows to conserve PPE, reduce contamination, and limit exposure. To conserve PPE and limit contamination from repeated donning and doffing, HCWs in moderate and high risk areas often remain in PPE during their entire shift. Shifts are limited to four hours to limit fatigue. Activities are bundled while in patient rooms to limit the number entries and exits. Phone and video communication with patients is encouraged to limit unnecessary exposure.
- Designate infection control specialists in care teams. Some hospitals have embedded infection control officers in care teams. These team members take on additional responsibility for monitoring and training the team for correct use of PPE. Other hospitals have instituted a “buddy system” in which team members check each other’s use of PPE before entering moderate and high risk areas.
- Separate suspected cases from each other and from confirmed cases. Many hospitals separate suspected cases from each other and from confirmed cases in order to prevent cross contamination.
- Plan for emergency high risk procedures in moderate risk zones. COVID-19 patients can experience rapid deterioration, and patients may back up in moderate risk zones because ICU beds are not available during a surge. Emergency high risk procedures are difficult to avoid even in moderate risk zones. This is especially true in EDs. Plans are in place to immediately manage PPE and disinfect these areas to mitigate the risk of contamination and spread.
High Risk
- Maintain highly trained teams dedicated to high risk situations. Because patients in high risk zones often require relatively complex care, special clinical teams are dedicated to the care of critically ill patients with COVID-10. These teams maintain a high level of infection control training and practice using drills and simulations.
- Limit community exposure. Dedicated COVID-19 clinical teams are staffed according continuous duty cycles (eg. two weeks on, one week off). While on duty, they are typically housed in hospital accommodations and discouraged from interacting with the community or non COVID-19 patients. They are required to have one, sometimes two negative COVID-19 PCR tests before returning to non COVID-19 duties. During their time off, they were housed separately from their families, and were screened for infection both upon leaving and before coming back on service.
Tailor PPE Standards Based on Exposure Risk
High PPE standards beyond traditional droplet and airborne precautions are in place for HCWs caring for COVID-19 patients, particularly critically ill patients in high risk zones. The SARS-CoV-2 virus is viewed as highly dangerous and transmissible, so these standards are in place not just to protect HCWs, but also to serve the public health purpose of limiting spread to the community. PPE is strategically applied based on levels of exposure risk.
Low Risk
Every individual in the hospital building is required to wear surgical masks regardless of symptoms or exposure history. These policies are based on the assumption of high community prevalence and risk of asymptomatic transmission. Masks are considered to be most effective when worn by potentially infected individuals to prevent transmission.
Moderate Risk
Risk of transmission where there are COVID-19 patients who do not require aerosol generating procedures is assumed to largely be from droplets from patients coughing, and from fomites (contaminated surfaces, including the exterior of PPE). However, the risk of aerosol transmission, albeit low, is still emphasized.
HCWs in moderate risk zones are required to wear:
- N95 respirator
- Gown
- Face mask / goggles
- Gloves
Some hospitals, when resources allow, have staff in full head to toe protective gear, including surgical caps or hoods, and shoe covers. Hair covers are particularly important for individuals with long hair, which can be fomites.
High Risk
Extreme precaution is taken in high risk zones given the presumed risk of airborne transmission. HCWs are required to cover their entire body to prevent aerosolized viral particles from contaminating skin and other body parts. Multiple layers of PPE are recommended to account for possible risk of PPE failure.
Key components of PPE in high risk situations include:
- N95 respirators and full face shields, or full face powered air-purifying respirators (PAPRs) when available
- Splash resistant suits that cover the entire body, including hair and shoes.
- In order to account for risk of PPE failure, redundancies are built into PPE guidelines, such as double gloving and wearing multiple layers of gowns.
Screening and Monitoring the Workforce
Healthcare workers are at higher infection risk than the general public. Regular screening of HCWs is done to prevent spread both within and from hospitals. Regular screening also allows infections to be caught early, which can reduce spread and improve clinical outcomes. Some hospitals have introduced the following policies for screening their workers:
- Self-monitor for symptoms. Staff who are regularly exposed to moderate and high risk situations are asked to monitor their own temperature and symptoms, sometimes before coming to work. If any symptoms are present — fever, chills, cough, dyspnea — they are isolated and tested. Some hospitals also perform checks during and at the end of shifts.
- Testing after high risk encounters. HCWs who have had a high-risk encounter (defined as 15 minutes in close contact with a confirmed case without appropriate PPE, or with a PPE failure such as a mask slipping) are taken off service for isolation and testing.
- Regular testing for high risk HCWs. HCWs who regularly work in moderate and high risk zones with confirmed cases are tested at regular intervals. These hospitals also test at the end of and before returning to service.
- Self-isolation or quarantine for HCWs who test positive. HCWs who test positive are quarantined and monitored for at least two weeks. They are allowed to return to work after this period if they were asymptomatic and tested negative twice, with tests 24 hours apart.
Conclusion
Protecting HCWs is critical to our fight against COVID-19. Experiences from successful model countries have led to comprehensive hospital infection control strategies. These include high standards for PPE and strict policies and processes that are implemented to minimize viral transmission and maintain a healthy, viable workforce.
We hope that discussion of the principles behind these interventions will inform how we approach infection control here in the United States.
We would like to thank Charles Prober, Oliver Aalami, Matt Lungren, Lisa Shieh, and Michelle Lin for their helpful guidance in the preparation of this article.
We would also like to thank Tian Wu and Francis Ho for sourcing information; Alice Lin for organizing the Samsung Medical Center Webinar; and Kelly Seelig for assisting design.
Sources
- Zhejiang University School of Medicine. Handbook of COVID-19 Prevention and Treatment
- World Health Organization. Rational use of personal protective equipment (PPE) for coronavirus disease (COVID-19). March 19, 2020.
- World Health Organization. Operational considerations for case management of COVID-19 in health facility and community. March 19, 2020.
- OSHA, Guidance on Preparing Workplaces for COVID-19
- Centers for Disease Control and Prevention. Interim Infection Prevention and Control Recommendations.
- Samsung Medical Center presentation (Samsung Medical Center, South Korea)
- Guo, Leon. Taiwan’s Healthcare Workers in COVID-19: presentation. National Taiwan University.
- Analysis of 25,000 Lab-confirmed COVID-19 Cases in Wuhan: Epidemiological Characteristics and Non-pharmaceutical Intervention Effects, Xihong Lin, Harvard School of Public Health and Dept of Statistics, Harvard University
